The present invention relates generally to computer interface circuits, and more specifically to a wireless interface system using a plurality of remote input devices to control a computer.
Present-day computers commonly utilize a plurality of input devices with a keyboard, a pointing device such as a mouse, and in many cases, a joystick to control their operation. These input devices are usually located in close proximity to the computer and are connected to the computer by cables. There are certain applications where it is advantageous to have the keyboard, pointing device, and joystick located remotely at a substantial distance from the computer. In such cases it may be difficult, impractical, or undesirable to connect the remotely located devices by cables. To overcome these difficulties, several types of wireless keyboards have been made, and several types of wireless pointing devices have been made.
For example, U.S. Pat. No. 4,754,268 by Mori (1988) describes a wireless mouse apparatus. This apparatus includes a transmitter for sending the data from the mouse to the receiver connected to the computer.
U.S. Pat. No. 4,917,516 by Retter (1990) describes a combination keyboard and mouse data entry system where the mouse is physically a part of the keyboard unit. This device sends two independent data streams to the computer over two separate data cables.
U.S. Pat. No. 5,189,543 by Lin, et. al. (1993) describes an infra-red wireless keyboard system.
U.S. Pat. No. 5,305,449 by Ulenas (1994) describes a keycode/pointing device conversion adapter which converts mouse motion signals into cursor signals by activating keyboard cursor keys. This device allows for the use of the pointing device through the normal keyboard cable and keyboard interface port of the computer. However, because this device converts the pointing device motion signals into keyboard cursor signals, it is not possible to separate out the pointing device motion signals from the true keyboard cursor signals once they reach the computer, and no attempt is made to do so. This has a great disadvantage because most computer software either will not operate at all, or will operate with greatly reduced functionality if the pointing device commands are given by keyboard cursor signals instead of directly by the pointing device motion signals. This conversion adapter does not allow for the pointing device motion signals to be delivered to the pointing device input port of the computer in an unmodified form.
U.S. Pat. No. 5,406,273 by Nishida, et al. (1995) describes an apparatus which includes both a keyboard hardwired to the data processing system and a second keyboard connected via a wireless link.
There are numerous infra-red wireless joystick devices commercially available today, such as the VictorMaxx VIR one. All of the known conventional systems only provide for the operation of a single input device, and have not provided for the operation of two or more wireless input devices.
Accordingly, several objects and advantages of the present invention are:
(a) to provide a wireless interface system which will accept inputs from a keyboard, a pointing device, and a joystick, either separately or in combination;
(b) to provide an apparatus to encode the data from the input devices and deliver the encoded data to the transmitter;
(c) to provide a single wireless communication link comprising a transmitter and a companion receiver, which is capable of sending the data from the encoding apparatus, and receiving the data that has been transmitted, thus allowing the communication link to be shared by two or more input devices;
(d) to provide an apparatus to decode the data from the receiver, such that the decoding apparatus is able to determine the source of the data from the remote input device;
(e) to provide a set of data multiplexer units to take the data from the data decoding apparatus and multiplex it with like data coming from a set of local input devices;
(f) to provide a suitable set of output interfaces to take the data from the multiplexer units and couple the data to the computer in a manner appropriate for the computer input ports;
(g) to provide a method whereby the keyboard data which originates with the remote keyboard is delivered to the keyboard input port of the computer in an unmodified form;
(h) to provide a method whereby the pointing device data which originates with the remote pointing device is delivered to the pointing device input port of the computer in an unmodified form; and
(i) to provide a method whereby the joystick signals which originate with the remote joystick are delivered to the joystick input port (more commonly called the game port) of the computer in an unmodified form.
Further objects and advantages are to provide a single wireless communication link which is lighter in weight, less costly to produce, and consumes less electrical power than an approach based on using a multiplicity of transmitters and receivers, where each input device uses its own individual transmitter and receiver for its communication to the computer.
Still further objects and advantages are to provide a method to allow multiple remotely located input devices, each with its own transmitter, to share a single frequency and to share a single receiver, so that each remotely located device is able to send information to the receiver in a time division multiplexed manner.
Still further objects and advantages are to provide a wireless communication link based on using a single transmitter so that any degradation in performance caused by interference from a multiplicity of transmitters is avoided. Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.
The present invention addresses these objects and advantages.
A method and system for a wireless interface system is disclosed. The wireless interface system comprises a plurality of input ports for coupling data from a plurality of input devices and an encoder means for encoding said data from said input ports. The interface system further includes a transmitter means for transmitting a set of signals corresponding to the result of said encoding means and a receiver means for receiving said set of signals from said transmitting means. The interface system further includes a decoder means for decoding data from said receiving means and a plurality of output interfaces for coupling the output of said decoder means to a plurality of computer input ports. Each of said output interfaces corresponds to a computer input port of like type. The said plurality of input devices share a single wireless communication link to provide said data to said computer input ports. A system in accordance with the present invention allows for a user to have a keyboard, pointing device and joystick device remotely located from a computer and still share a single wireless communication link to send its data to the computer.